This invention relates to a system that delivers horticultural agents including nutrients, fertilizers, insecticides, and herbicides to a plant's root system effectively and efficiently. This invention also relates to a delivery system that reduces and/or prevents the incidence of weeds.
Three "Current Trade Supported Methods" for applying granular fertilizer around a plant currently in use include the following: 1) measuring a proper amount of fertilizer based upon a plant's size and type and then spreading loose fertilizer granules on the top surface of the ground/container around a plant; 2) measuring a proper amount of fertilizer based upon a plant's size and type and then mixing loose fertilizer granules with a plant's back-fill soil; and 3) measuring a proper amount of fertilizer based upon a plant's size and type and then spreading loose fertilizer granules at the base of the hole in the ground or container where a plant is to be placed.
Other methods of applying fertilizers to a plant's root system include the following: 4) placing a pre-measured package containing fertilizer on the top surface of the ground around a plant (see U.S. Pat. Nos. 4,627,191, 3,857,195, 1,554,865, and 3,005,287); 5) pushing into the ground a fertilizer stick (see U.S. Pat. No. 4,014,675; 6) placing a pre-measured fertilizer tablet in the ground around the plant (see U.S. Pat. No. 4,055,974); 7) placing a plastic sheet incorporating a water-soluble plant nutrient on the surface of the ground (see Pat. No. 3,384,993); 8) placing a plant activating device under a plant (see Pat. No. 1,988,307); and 9) pouring a water-soluble liquid fertilizer around the base of the plant.
A disadvantage of several of the foregoing methods is that they require significant involvement of the user in determining and applying fertilizer dosage. In addition to the risk associated with measurement errors, there is also a risk the user will spread the fertilizer granules unevenly around the plant, in the back-fill soil, or at the bottom of a hole. In each of these methods there is also a risk of applying too much or too little plant nutrients (timed-release fertilizer). Even if the correct quantity of fertilizer is applied, then there is a risk of applying it unevenly. Other disadvantages emanate from the fact that a water-soluble fertilizer's nutrients are easily leached from the soil, thereby requiring frequent feeding. Also, the mixing of water and fertilizer is time-consuming, cumbersome, messy, and potentially hazardous.
A disadvantage of using a pre-measured package as disclosed in, for example, method 4 above, is that it is not economical. In addition, method 4's product design requires a pre-measured fertilizer package to be placed on the top surface of the ground and not next to the plant's root system. Also, the use of timed-release plant nutrients in a packet type of container would result in a concentration of fertilizer in contrast to a preferred design whereby the granular fertilizer is evenly spaced and evenly available to all the plant's root system.
Disadvantages of using a fertilizer stick (as identified in method 5 above) include that it provides nutrients only at the point it is inserted into the soil. Depending upon the size of the plant to be fertilized, multiple fertilizer sticks are recommended, with such sticks to be positioned equally spaced around the plant. Due to its spacing, the fertilizer does not reach all of the plant's root system equally. Also, due to the limited time fertilizer is made available to the plant's root system, usually 60 days, additional sticks must be inserted into the ground on a somewhat regular and frequent basis.
The disadvantages of using a pre-measured fertilizer tablet (as identified in method 6 above) are similar to the disadvantages of using a fertilizer stick. The availability of nutrients to the plant's root system is limited to roots closest to the fertilizer tablet; proper feeding requires multiple tablets to be used; and due to the fertilizer tablet's design, multiple feedings are necessary approximately every 60 days.
A plastic sheet incorporating a water-soluble plant nutrient on the surface of the ground (as identified in method 7 above), if wrapped around the plant's root system, would cause the plant to die. In addition, time-released fertilizers could not be incorporated into the plastic sheet due to the thickness of the plastic film, the extrusion process, and the average diameter of the timed-release fertilizer granules.
Timed-release fertilizers were first developed and/or introduced around 1985. Since then the fertilizer and nursery industries have provided timed-release fertilizer in granular form, each grain containing plant nutrients necessary for feeding a plant's root system. Methods 1, 2 and 3 above, when using timed-release fertilizers to feed a plant's root system, have been the methods recommended by the trade and in most common use by the consumer.
There are three primary disadvantages in using the existing "Trade Supported Methods" for applying timed-release fertilizers to a plant's root system. One disadvantage is that the consumer must measure the amount of fertilizer needed and, in doing so, there is a risk that the consumer will measure incorrectly and apply or distribute too much or too little fertilizer. When this happens, a plant's root system is either burned by too much fertilizer or stunted by too little fertilizer. A second disadvantage is that the consumer always distributes the granular fertilizer by hand. This method results in an uneven and poorly spaced distribution of granular fertilizer, thereby overfeeding some of a plant's roots while underfeeding others. A third disadvantage in using one of the existing methods is that a plant's root system does not have timed-release fertilizer granules placed in direct proximity to all of a plant's root system. The result is that very few roots of a plant have immediate nutrient access because of the distance between the fertilizer granule and the roots of the plant.